One new feature of iPhone OS 3.0 is the ability to do tethering without additional software. Unfortunately, this feature is not enabled in US. For those people whose iPhone carriers that support it, here is a tip. If you want to use tethering via USB, you need to install iTunes 8.2 on the computer. iTunes 8.2 provides necessary driver for your iPhone to act as a Mobile Device Ethernet. Otherwise, the phone will be recognized as a camera.